Field of the Invention
The present disclosure relates to a system, for example an automated system, for interfacing, processing, preparing, delivering to and/or collection of products from a micro-processing chip.
Description of the Related Art
A system performing sample preparation using cartridges (i.e. concentration of a solute from large 1 mL volume to small 5 uL volume using an anion exchange resin) has been used to interface with microfluidics. An example of such as system is set forth in Elisarov et al., J. Nucl Med 51(2): 282 (2010), which is hereby incorporated herein in its entirety by reference. However, this system utilized liquid valves, which resulted in the system being more expensive, the fluid path requiring cleaning rather than being disposable, and required the system to have larger size and larger surrounding apparatus.
Commercially available rotary valves with small volume injection loops have been used to achieve similar results to the above system, but still require much more space, undercutting the benefits of the microfluidics in the rest of the chemical processing system. Furthermore, these systems, however do not interface digital microfluidics chips, do not utilise electrowetting with solvent exchange, and do not utilize an integrated platform for digital microfluidics or a purely liquid-valve free system.
Reagents utilized with the above mentioned systems are typically loaded manually to the chip, leading to chemical and radiation exposure hazards, and require greater time, effort and expertise. The common approach of pre-loading reagents into on-chip or off chip reservoirs is not feasible for this application due to volatility of many reagents, concerns of cross-contamination, and the possibility of being incompatible with certain organic solvents.
Some automated extraction of product from a digital microfluidics chip into a capillary for nanospray injection has been reported, for example, by Shin et. al, (Anal. Chem. 2012, 84, 3731-3738, which is hereby incorporated herein in its entirety by reference) by introducing a glass capillary into the gap between chip substrates. Liquid was removed from the chip using the capillary effect in the inside walls of the capillary, and was ejected by applying 1.7-2.2 kV of potential, which creates a nanospray. Other approaches to removal of products/droplets from chips includes bringing the liquid droplet in contact with another preferentially wetting surface (See Yi, Sensors and Actuators, 2004, 114 (2-3), 347-354, which is hereby incorporated herein in its entirety by reference). However, one of the disadvantages of these approaches is that they are not suitable for applications where the collected product needs to be further processed for more synthesis steps, purification or quality control before use, as is commonly required from chemical synthesis products, especially those for use in biological systems.